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This study aimed to investigate the effect of cold atmospheric plasma (CAP) on the physicochemical and functional properties of myofibrillar protein isolated from Alaska pollock (Theragra chalcogramma) muscle. Free sulfhydryl content, surface hydrophobicity, turbidity, differential scanning calorimetry, SDS‐PAGE, heat‐induced myofibrillar protein gel properties and water holding capacity were determined to evaluate the effect of CAP treatment on protein properties. CAP treatment from 10 to 60 kV for 10 min significantly (P

This paper examined the fracture behavior of fiber bundles in moso bamboo by means of microscopic techniques. The fracture characteristics of fiber bundles in the tensile and compressive layer in response to three-point bending were analyzed. Results indicated that cracks propagate in a tortuous manner in three-point bending. The failure modes of fiber bundles were different in the tensile and compressive layer in bending. Specifically, two types of fiber fraction were observed in the tensile layer, namely smooth fracture and multistage delaminating. Three fracture modes were found in the compressive layer: minor cracks immediately under the area of loading head; localized fiber cracks in tension and delamination between fibers. Unique cellular arrangement, micro-cracks and crack deflection can increase elasticity, failure strength and flexibility of bamboo. The failure behavior of fiber bundles and tortuous crack propagation presented in this study can provide insights into the development of advanced bio-inspired materials and bamboo composites.

The ability to reversibly manipulate the surface nature of luminescent nanoparticles upon external stimulation enables the development of advanced optical probes for biological sensing and data encoding. Herein, we report the synthesis of a new class of smart carbon dots (CDs) via surface modification of amine-enriched CDs with CO2-responsive groups of amidine. We present that alternative CO2 and N2 bubbling can not only lead to a reversible phase transfer of the CDs between an organic phase and an aqueous phase but also give rise to a corresponding reversible luminescence change between blue and cyan-green. We attribute these observations to changes in both the surface chemistry and the emission states of the CDs triggered by the alternative CO2/N2 introduction. We also find a similar luminescence change of the CDs upon alternative exposure to a humid vapor of CO2 and a mixture of NH3 and N2 at room temperature, allowing them to be used as a new class of optical materials for optical encoding.

The aim of the study was to investigate the effect of hydroxyl-radical on myofibrillar protein properties. Myofibrillar protein isolated from Alaska pollock muscles were incubated with oxidant agents containing different H2O2 concentrations of 0, 0.1, 1, 5, 10 and 20 mmoL/L for 1, 3 and 5 h respectively. Incubation at higher concentrations of H2O2 induced a significant decrease of protein total sulfhydryl group and an increase in protein carbonyl content in the myofibrillar fraction. Moderate H2O2 concentration (1 mmoL/L) enhanced water-holding capacity and textural properties of a gel, while lower (0.1 mmoL/L) and higher (5, 10 & 20 mmoL/L) H2O2 concentrations significantly reduced the water-holding capacity. At higher H2O2 concentration, oxidized gel revealed some resistance toward the change in gel properties. Additionally, the results from SDS-PAGE and microstructure confirmed the structural changes through aggregation and denaturation of myofibrillar components that induced changes on gelation of myofibrillar protein. The whiteness of the myofibrillar protein gel decreased significantly (p

Over years, various biological constituents are isolated from Traditional Chinese Medicine and confirmed to show multifunctional activities. Magnolol, a hydroxylated biphenyl natural compound isolated fromMagnolia officinalis, has been extensively documented and shows a range of biological activities. Many signaling pathways include, but are not limited to, NF-κB/MAPK, Nrf2/HO-1, and PI3K/Akt pathways, which are implicated in the biological functions mediated by magnolol. Thus, magnolol is considered as a promising therapeutic agent for clinic research. However, the low water solubility, the low bioavailability, and the rapid metabolism of magnolol dramatically limit its clinical application. In this review, we will comprehensively discuss the last five-year progress of the biological activities of magnolol, including anti-inflammatory, antimicroorganism, antioxidative, anticancer, neuroprotective, cardiovascular protection, metabolism regulation, and ion-mediating activity.

A series of Co2+:ZnSe and Co2+:ZnSe/ZnSe nanocrystals emitting mid-infrared (mid-IR) fluorescence centered at around 3.4 and 4.7 μm were successfully synthesized via a simple hydrothermal method. The core/shell structure and post-heat treatment under reducing atmosphere were adopted to decrease the nanocrystal’s surface quenching centers and defects and improve the mid-IR photoluminescence. By analysis of the X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy (TEM), high-resolution TEM, Fourier transform IR, absorption, and mid-IR emission measurements of serial concentrations of Co2+-doped ZnSe nanocrystals, the crystal phase, grain size, core/shell structure, distribution of Co2+ ions, impurities on the surface, and mid-IR emission performance were investigated in detail. By use of optimum Co2+ concentration, core/shell structure construction, and proper post-heat treatment, the mid-IR emission intensities of nanocrystals were enha...

The mesopore structures in polyacrylonitrile (PAN) fibers during dry-jet wet spinning process were investigated by high-resolution transmission electron microscopy (HRTEM) and image analysis utilizing the ultrathin section technique. The morphologies and dimension distribution of the mesopores in the surface and core regions of the nascent fibers and PAN fibers are presented. All fibers exhibited lamellar-like structures perpendicular to the fiber axis and the mesopores were distributed between the lamellae. For nascent fibers, the size and volume of the mesopores increased with increasing air gap and decreased with increasing drawing ratio. In addition, the widths of the mesopores were larger than their lengths. Consequently, the size and content of the mesopores in nascent fibers could be adjusted by controlling coagulation conditions. During the post-spinning process, the size and volume of the mesopores in PAN fibers decreased efficiently by hot drawing in a hot water washing bath, in hot steam chambers or on hot rollers. Moreover, the lengths of the mesopores were larger than their widths. In all fiber samples, the number and size of the mesopores in the core region were larger than those in the surface region. In addition, the mechanical properties of fibers were correlated with dimension of the mesopores. Their tensile strength increased with decreasing mesopore widths and lengths.

Polyetheretherketone (PEEK) is widely used in orthopedic and dental applications because of its similar mechanical properties to those of natural bones. However, the inferior osseointegration and bioinertness hamper the clinic application. The surface texture of biomaterials plays an essential role in controlling cell differentiation through affecting the cell-generated physical forces, thus improving the osseointegration of the substrate. In this work, argon PIII and subsequently hydrogen peroxide treatment are applied to construct the nanostructure on the PEEK surface. The in vitro results show that the cell adhesion, collagen secretion, and extracellular matrix (ECM) deposition can be enhanced on both nanostructured surfaces. The in vivo tests exhibit that the surface fabricated by physical-chemical treatment is more favorable for fibrous tissue filtration inhibition and osseointegration than that fabricated by argon PIII only. This work provides a candidate approach for improving the osseointegration ability of PEEK implant by constructing the nanostructure on its surface, which paves the way of applying PEEK in orthopedic and dental applications.

The development of earth-abundant catalysts for efficient hydrolysis of ammonia borane is of great importance in the conversion and utilization of hydrogen energy. Here, we report the synthesis of SiO2-encompassed Co@N-doped porous carbon assemblies as a new type of recyclable catalyst for the purpose by calcination of zeolitic imidazolate framework-67@SiO2 microtubes at high temperatures under an N2 atmosphere. We find that the surface layer of SiO2 in the precursor microtubes is essential for the production of efficient catalysts by supplying an additional surface for Co nanoparticle dispersion in an effort to reduce their size. In addition, the SiO2 layer renders a highly ordered arrangement of Co@N-doped porous carbon within the catalysts, possibly allowing the ease of mass transfer of ammonia borane within the catalysts. The optimized catalysts obtained via calcination at 800 °C show a set of remarkable catalytic benefits, including a high hydrogen generation rate of 8.4 mol min–1 mol(Co)–1, a relati...

Excellent poly(acrylonitrile-co-itaconic acid) (99/1) (PAI) nascent fibers, which have an important role in preparing high-quality precursors for carbon fibers, were prepared by a dry-jet wet spinn...

The development of an ultrastable and efficient technology for H2 production is an important step in the utilization of renewable and clean energy. Herein, we report that hybrid water electrolysis, integrating the electrochemical reforming of benzyl alcohol (BA) and the H2 evolution reaction (HER), largely accelerates the kinetics and stability of H2 production over a hierarchical bifunctional catalyst couple of Mo–Ni alloy nanoparticles in 1.0 M KOH. The high-performance of the hierarchical Mo–Ni nanoparticle catalyst for both the HER and the BA oxidation not only eliminated the need for an ion-conducting membrane to separate the cathodic and anodic reactions to achieve nearly unity faradaic efficiences for the two reactions, but also allowed the reactions to be readily driven by low cell voltage in a two-electrode configuration. Specifically, the cell voltages required to deliver the benchmark current densities of 20, 50, and 100 mA cm−2 are as low as 1.40, 1.45, and 1.53 V, respectively. The membrane-free hybrid water electrolysis technology exhibits a set of advantages including long device lifetime, ease of H2 collection, and high efficiency, thus showing significant promise for practical H2 production, especially considering the fact that the device can be readily powered by a single-cell alkaline battery or a solar cell under natural sunlight irradiation.

Four-dimensional cone beam CT (4D-CBCT) imaging can provide accurate location information of real-time breathing for imaging-guided radiotherapy. How to improve the accuracy of 4D-CBCT reconstruction image is a hot topic in current studies. PICCS algorithm performs remarkably in all 4D-CBCT reconstruction algorithms based on CS theory. The improved PICCS algorithm proposed in this paper improves the prior image on the basis of the traditional PICCS algorithm. According to the location information of each phase, the corresponding prior image is constructed, which completely eliminates the motion blur of the reconstructed image caused by the mismatch of the projection data. Meanwhile, the data fidelity model of the proposed method is consistent with the traditional PICCS algorithm. The experimental results showed that the reconstructed image using the proposed method had a clearer organization boundary compared with that of images reconstructed using the traditional PICCS algorithm. This proposed method significantly reduced the motion artifact and improved the image resolution.

Curdlan/β-cyclodextrin (β-CD) composite hydrogels were prepared by using epichlorohydrin (ECH) and ethylene glycol diglycidyl ether (EGDGE) as cross-linkers respectively. The results showed that a ...

The large yellow croakers (Larimichthys crocea) are mainly present in the Chinese coast and near seas with high economic importance, but vulnerable to many diseases, especially in the breeding and aquaculture. The purpose of this research was to boost the innate immune system of the large yellow croaker by administering bitter peptides into their peritoneal cavity. Total 120 Juvenile of large yellow croakers in very even weight of 60 g were divided into 4 different groups in 200/300 L of water tank, respectively. Fish growth were observed for 3 months before and after different treatments. The bitter peptides from pepsin hydrolysis were applied because they possess the highest bitter sensory scores. The blood of fish from the different groups was collected and tested for different immune parameters to evaluate the effectiveness of bitter peptides as immune stimulants after administration for 8 weeks. The average ratio of leukocytes/total blood cells (%) for control was found at 14.6%, for the low dose of bitter peptides 0.6 mg/fish was at 29.3%, for middle dose of 1.2 mg/fish was at 35%, and high dose of 2.4 mg/fish was at 30%. The lysozyme assay showed that the OD (optical density) units of relative progress lysis activity at 60 min were 0.17, 0.101, 0.307 and 0.198, respectively. Similarly in the same order as in phagocyte assay, most importantly the middle dose (1.2mg/fish) gave the highest survival rate throughout the assay. The results showed that bitter peptides can be used as immune boosters for the yellow croakers and the optimum dose was 1.2 mg/fish due to both leukocytes and lysozyme activity in the treated samples increased significantly compared with the control group. According to the results obtained, we suggest that the incorporation of middle dose of bitter peptides into fish feeds may reduce the fish diseases in aquaculture, at least for large yellow croakers.

Bamboo fiber composite (BFC) is a unidirectional and continuous bamboo fiber composite manufactured by consolidation and gluing of flattened, partially separated bamboo culm strips into thick and dense panels. The composite mechanical properties are primarily influenced by panel density, its variation and uniformity. This paper characterized the horizontal density distribution (HDD) within BFC panels and its controlling factors. It revealed that HDD follows a normal distribution, with its standard deviation (SD) strongly affected by sampling specimen size, panel thickness and panel locations. SD was lowest in the thickest (40 mm) panel and largest-size (150 × 150-mm2) specimens. There was also a systematic variation along the length of the BFC due to the tapering effect of bamboo culm thickness. Density was higher along panel edges due to restraint from the mold edges during hot pressing. The manual BFC mat forming process is presented and found to effectively minimize the density variation compared to machine-formed wood composites. This study provides a basic understanding of and a quality control guide to the formation uniformity of BFC products.

The authors have requested that this preprint be removed from Research Square.

Assessing renal function accurately is important for human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) patients. Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) recommended three equations to calculate estimated glomerular filtration rate (eGFR). There is evidence that eGFR based on the combination of serum creatinine and cystatin C is the most accurate of the three equations. But there is limited data on the comparison of three CKD-EPI equations in Chinese HIV/AIDS patients. The aim of our study was to compare the three CKD-EPI equations in Chinese HIV/AIDS population and assess renal function. Cross-sectional, single center, prospective study. One hundred seventy two Chinese adult HIV/AIDS patients were enrolled, including 145 (84.3%) males and 27 (15.7%) females. Mean age was 40(±12) years old. Overall mean eGFR based on serum creatinine, cystatin C and the combination of the 2 markers was 112.6(±19.0) mL/min/1.73 m2, 92.0(±24.2)mL/min/1.73 m2, and 101.7(±21.8)mL/min/1.73 m2, respectively (P = .000). The eGFR calculated by serum creatinine alone is higher than eGFR calculated by combination of serum creatinine and cystatin C, and eGFR calculated by cystatin C individual is lower than eGFR calculated by combination of the 2 markers. Of the 3 CKD-EPI equations, the CKD-EPIscr-cys equation may have the most accuracy in evaluating renal function in Chinese HIV/AIDS patients while the CKD-EPIscr equation may overestimate renal function and the CKD-EPIcys equation may underestimate renal function.

Purpose To characterize longitudinal changes in macular microvasculature as quantified from optical coherence tomography angiography (OCTA) metrics in primary open-angle glaucoma (POAG) eyes with and without high myopia. Methods In total, 63 and 61 POAG eyes with and without high myopia, respectively, underwent swept-source OCTA imaging in at least four follow-up visits at an ophthalmic center, with a scanning protocol of 3- × 3-mm centered at the fovea. The foveal avascular zone (FAZ) area, FAZ circularity, and vessel density (VD) in both the superficial (SCP) and deep capillary plexuses (DCP) were measured. The rate of change in macular OCTA metrics over time was estimated using linear mixed-effects models in both groups of POAG eyes. Results The mean follow-up time and number of visits were 27.72 ± 8.57 months and 8.5 (8 to 13) times, and 30.95 ± 10.19 months and 10 (8‒13) times in POAG eyes with and without high myopia, respectively. VD in the DCP reduced significantly more quickly in POAG eyes with high myopia than in those without high myopia (−5.14%/year vs. −3.71%/year, P = 0.008). Moreover, lower baseline VD in the DCP was significantly associated with faster VD reduction in POAG with high myopia eyes (P < 0.001). Conversely, the VD reduction rate in the SCP, FAZ area, and FAZ circularity in both the SCP and DCP were similar in both groups (all Ps > 0.05). Conclusions VD in DCP reduced significantly more quickly in POAG eyes with high myopia over time. Density in the DCP reduced more quickly when baseline VD was low.

The wide adoption of Building Automation System (BAS) and Building Energy Management System (BEMS) has provided building professionals with large amounts of building operational data for knowledge discovery. Considering the intrinsic complexity in building operations and common faults in data collections, data preprocessing has been recognized as an indispensable step in building operational data analysis. It can be used to enhance data quality by removing outliers and missing values, ensure data compatibility with data mining algorithms, and improve the sensitivity and reliability in data analysis. This study provides a comprehensive review on data preprocessing techniques in analyzing massive building operational data. The paper firstly reviews techniques for conventional data preprocessing tasks, including missing value imputation, outlier detection, data scaling, reduction and transformation. Afterwards, the paper proposes promising techniques for advanced data preprocessing tasks, including data partitioning, feature engineering, data augmentation and transfer learning. Based on the critical review, future research directions and potential applications for building data analysis has been summarized. This paper can provide a general picture on data preprocessing methods for building operational data analysis. The insights obtained are valuable for the development of advanced data-driven solutions for smart building energy management.

The ability of carbon dots (CDs) to emit afterglow emission in addition to fluorescence in response to UV-to-visible excitation allows them to be a new class of luminescent materials. When compared with traditional organic or inorganic afterglow materials, CDs have a set of advantages, including small size, ease of synthesis, and absence of highly toxic metal ions. In addition, high dependence of their afterglow color output on temperature, excitation wavelength, and aggregation degrees adds remarkable flexibility in the creation of multimode luminescence of CDs without the need for changing their intrinsic attributes. These characteristics make CDs particularly attractive in the fields of sensing, anticounterfeiting, and data encryption. In this review, we first describe the general attributes of afterglow CDs and their fundamental afterglow mechanism. We then highlight recent strategic advances in the generation or activation of the afterglow luminescence of CDs. Considerable emphasis is placed on the summarization of their emergent afterglow properties in response to external stimulation. We further highlight the emerging applications of afterglow CDs on the basis of their unique optical features and present the key challenges needed to be addressed before the realization of their full practical utility.

Topology control in large-scale power grid system is a challenging problem because of the enormous state and action space. This paper proposes an efficient two-stage topology control framework to make a trade off between speed and accuracy. The framework consists of two components: a fast nominator for candidate actions generation and a slower but more accurate ranker for final action selection. Differing from previous works, this paper formulates candidates generation as a sequential decision making process, so as to take full advantage of information feedback from the ranker to guide the subsequent candidates generation process. To achieve this, the nominator is built as a GRU-based agent and is trained via reinforcement learning (RL). Experiment results show that the nominator is able to capture valuable information from historical feedback from ranker, and our method outperforms traditional methods on L2RPN NeurIPS 2020 Adaptability Track benchmark.

Abstract The progression of prion diseases is accompanied by the accumulation of prions in the brain. Ablation of microglia enhances prion accumulation and accelerates disease progression, suggesting that microglia play a neuroprotective role by clearing prions. However, the mechanisms underlying the phagocytosis and clearance of prion are largely unknown. The macrophage scavenger receptor 1 (Msr1) is an important phagocytic receptor expressed by microglia in the brain and is involved in the uptake and clearance of soluble amyloid-β. We therefore asked whether Msr1 might play a role in prion clearance and assessed the scavenger function of Msr1 in prion pathogenesis. We found that Msr1 expression was upregulated in prion-infected mouse brains. However, Msr1 deficiency did not change prion disease progression or lesion patterns. Prion deposition in Msr1 deficient mice was similar to their wild-type littermates. In addition, prion-induced neuroinflammation was not affected by Msr1 ablation. We conclude that Msr1 does not play a major role in prion pathogenesis. Key messages Msr1 expression is upregulated in prion-infected mouse brains at the terminal stage Msr1 deficiency does not affect prion disease progression Msr1 does not play a major role in prion clearance or prion pathogenesis Microglia-mediated phagocytosis and clearance of Aβ and prion may adopt distinct molecular pathways

IntroductionMyopic maculopathy and glaucoma belong to the most common causes of irreversible blindness worldwide and, having an ocular axial elongation as one of their main risk factors, can occur together. The detection of glaucomatous optic neuropathy (GON) in highly myopic eyes is clinically and technically difficult, and there is no information available, neither about the natural course of GON or about the course of GON under intraocular pressure-lowering therapy. We therefore designed this study to explore the natural course of GON in highly myopic eyes.Methods and analysisIn this single-centred longitudinal registry cohort study, 813 highly myopic individuals will be recruited and undergo detailed ophthalmic examinations. High myopia is defined by a myopic refractive error of ≥−6 D or an axial length of ≥26.5 mm. GON is defined by a glaucomatous appearance of the optic nerve head or glaucomatous visual field (VF) defects. GON progression is defined by either change of the optic disc or VF.Ethics and disseminationEthical approval has been obtained from the ethical committee of the Zhongshan Ophthalmic Center (ZOC), Sun Yat-sen University, China (ID: 2019KYPJ079). All the participants are required to provide informed consents. Results will be disseminated through scientific meetings and published in peer-reviewed journals. The data will be deposited at the clinical research centre in ZOC using electronic data capture system, and a copy of paper files will also be kept. Only members of the project team will have access to these data.Trial registration numberNCT04302220.

Background Both COVID-19 and influenza A contribute to increased mortality among the elderly and those with existing comorbidities. Changes in the underlying immune mechanisms determine patient prognosis. This study aimed to analyze the role of lymphocyte subsets in the immunopathogenesisof COVID-19 and severe influenza A, and examined the clinical significance of their alterations in the prognosis and recovery duration. Methods By retrospectively reviewing of patients in four groups (healthy controls, severe influenza A, non-severe COVID-19 and severe COVID-19) who were admitted to Ditan hospital between 2018 to 2020, we performed flow cytometric analysis and compared the absolute counts of leukocytes, lymphocytes, and lymphocyte subsets of the patients at different time points (weeks 1–4). Results We reviewed the patients’ data of 94 healthy blood donors, 80 Non-severe-COVID-19, 19 Severe-COVID-19 and 37 severe influenza A. We found total lymphocytes (0.81 × 109/L vs 1.74 × 109/L, P = 0.001; 0.87 × 109/L vs 1.74 × 109/L, P < 0.0001, respectively) and lymphocyte subsets (T cells, CD4+ and CD8+ T cell subsets) of severe COVID-19 and severe influenza A patients to be significantly lower than those of healthy donors at early infection stages. Further, significant dynamic variations were observed at different time points (weeks 1–4). Conclusions Our study suggests the plausible role of lymphocyte subsets in disease progression, which in turn affects prognosis and recovery duration in patients with severe COVID-19 and influenza A.

Objective The real-time polymerase chain reaction (RT-PCR) test is recommended for the diagnosis of COVID-19 and provides a powerful tool to identify new infections and facilitate contact tracing. In fact, as the prevalence of COVID-19 decreases, this RT-PCR testing remains as the main preventive measure to avoid rebound. However, inconsistent results can lead to misdiagnoses in the clinic. These inconsistencies are due to the variability in (1) the collection times of biological samples post infection, and (2) sampling procedures. Methods We applied the Kaplan–Meier method and multivariate logistic regression on RT-PCR results from 258 confirmed patients with COVID-19 to evaluate the factors associated with negative conversion. We also estimated the proportion (%) of negative conversion among patients who had tested twice or more, and compared the proportions arising from oropharyngeal swabs, sputum, and combined double testing, respectively. Main results The proportion of negative conversion was 6.7% on day 4, 16.4% on day 7, 41.0% at 2 weeks, and 61.0% at 3 weeks post-admission. We also found that 34.1% and 60.3% of subjects had at least one negative RT-PCR result on days 7 and 14 after the onset of symptoms, respectively. The proportion of negative conversions following sputum testing was higher than that from oropharyngeal swabs in the early stages but this declined after the onset of symptoms. Conclusion In the absence of effective treatments or vaccines, efficient testing strategies are critical if we are to control the COVID-19 epidemic. According to this study, early, consecutive and combined double testing, will be the key to identify infected patients, particularly for asymptomatic and mild symptomatic cases. These strategies will minimize misdiagnosis and the ineffective isolation of infected patients.

This article explores the pathogenesis of sepsis AKI, and seeks to protect the acute damage of sepsis tissues and organs. This study is to prepare a rat sepsis-induced AKI model by CLP, and to observe the pathological changes of kidney tissue and the function of kidney changes, and observe the effect of siRNA nanoparticles on its intervention, preliminary explore the protective effect and possible mechanism of siRNA nanoparticles on AKI in sepsis rats, and provide more information for the clinical treatment of siRNA nanoparticles in sepsis theoretical and experimental basis. We analysis the benefit and deficiency of nuclear factor

OBJECTIVE: To achieve low-dose digital breast tomosynthsis (DBT) projection recovery using penalized weighted least square algorithm incorporating accurate modeling of the variance of the projection data and noise correlation in the flat panel detector. METHODS: Models were established for the quantal noise and electronic noise in the DBT system to construct the penalized weighted least squares algorithm based on noise correlation for projection data restoration. The filter back projection algorithm was then used for DBT image reconstruction. RESULTS: The reconstruction results of the ACR phantom data at different dose levels showed a good performance of the proposed method in noise suppression and detail preservation. CNRs and LSNRs of the reconstructed images from the restored projections were increased by about 3.6 times compared to those of reconstructed images from the original projections. CONCLUSIONS: The proposed method can significantly reduce noise and improve the quality of DBT images.

BACKGROUND Education informatization is still in the early stage in China. The sudden outbreak of the COVID-19 pandemic led medical educators to passively incorporating information technology for remote medical teaching, in which challenges and opportunities have co-existed. OBJECTIVE The objectives of this study were to (1) explore the medical educators' perception and experience of online teaching in medical education before and after emergency remote teaching (ERT) experience during the COVID-19 pandemic; (2) illustrate the medical educators' satisfaction with the contribution of online teaching on medical teaching, and (3) reveal the main challenges medical educators met when they conduct the ERT during the COVID-19 epidemic, and to demonstrate whether the challenges are different by age or gender including some other factors. METHODS A web-based questionnaire was disseminated to the faculty of medical education departments at higher institutions in China. The collected quantitative data of the questionnaire were analyzed by using the SPSS software package. Descriptive statistics were conducted on demographic data and the perception and experience of medical educators before and after the COVID-19 were shown as the frequencies and percentages, while the teachers' opinions on contribution of online teaching on medical education were analyzed by descriptive statistics with means and standard deviations. Multiple response analysis combined with crosstabulation chi-square test was applied, and a P-value RESULTS A total of 26 medical educators (65.38%, n=17 female and 34.62%, n=9 male) were valid participants. Total 57.69% (n=15) of them had used web-based teaching before the COVID-19 pandemic, whereas 43.21% (n=11) had not. The agreement level on the teaching effect of online teaching was medium, with a mean value of 2.55 (range from 1-5). The first two difficulties medical teachers came across in online teaching were the web-based instructional design (27%), and the unfamiliarity with web-based teaching tools (25 %). No significant difference in the types of difficulties encountered by different ages (P=0.969) or gender (P = 0.873) in online teaching. CONCLUSIONS A total of 26 medical educators (65.38%, n=17 female and 34.62%, n=9 male) were valid participants. Total 57.69% (n=15) of them had used web-based teaching before the COVID-19 pandemic, whereas 43.21% (n=11) had not. The agreement level on the teaching effect of online teaching was medium, with a mean value of 2.55 (range from 1-5). The first two difficulties medical teachers came across in online teaching were the web-based instructional design (27%) and the unfamiliarity with web-based teaching tools (25 %). No significant difference in the types of difficulties encountered by different ages (P=0.969) or gender (P = 0.873) in online teaching.

Falls are a major public health concern in today&rsquo, s aging society. Virtual reality (VR) technology is a promising method for reducing fall risk. However, the absence of representations of the user&rsquo, s body in a VR environment lessens the spatial sense of presence. In terms of user experience, augmented reality (AR) can provide a higher degree of presence and embodiment than VR. We developed an AR-based exergame system that is specifically designed for the elderly to reduce fall risk. Kinect2.0 was used to capture and generate 3D models of the elderly and immerse them in an interactive virtual environment. The software included three functional modules: fall risk assessment, cognitive&ndash, motor intervention (CMI) training, and training feedback. The User Experience Questionnaire (UEQ-S) was used to evaluate user experience. Twenty-five elders were enrolled in the study. It was shown that the average scores for each aspect were: pragmatic quality score (1.652 &plusmn, 0.868), hedonic quality score (1.880 &plusmn, 0.962), and overall score was 1.776 &plusmn, 0.819. The overall score was higher than 0.8, which means that the system exhibited a positive user experience. After comparing the average score in a dataset product of UEQ-S Data Analysis Tool, it was found that the pragmatic quality aspect was categorized as good, while the hedonic quality aspect was categorized as excellent. It revealed a positive evaluation from users.

The nonlinear response of wide bandgap oxide thin films gradually emerges and attracts attention with the development of an ultra-short and ultra-intense laser. In Z-scan technique, due to the extremely lower nonlinear response of thin film compared with the common substrate, it isn’t easy to measure the multiphoton absorption coefficient of wide bandgap oxide thin films. In this study, a method is proposed to suppress the substrate impact and improve the thin film measurement sensitivity. To make the thin film nonlinear intensity dominate the total intensity, including unwanted substrate impact, material and thickness of the substrate are analyzed. Considering the nonlinear effects of different substrates and the adhesion between the substrate and the thin film, 50 μm MgF2 and quartz glass are selected as the substrate for deposition. The nonlinear intensity of substrate is suppressed to at least 80% of the whole element or can even be ignored so that the normalized transmittance of the thin film can be obtained effectively. The two-photon and three-photon absorption coefficients of HfO2, Al2O3, and SiO2 thin film are measured at different wavelengths. The nonlinear absorption response measurements of wide bandgap oxide thin films can advance the design and fabrication of low-loss photonic devices in ultra-fast lasers.

Background PPVI 1 and PPⅦ 2 were a group of Pennogenin compounds extracted from the Paris polyphylla and caused hepatotoxicity in human, while the potential underlying mechanism was unclear. Purpose To evaluated the adverse effects of PP VI and PP Ⅶ on the liver in the zebrafish. Method In this study, 4dpf zebrafish were used for acute toxicity test, LC0 was calculated, and 1/2LC0 and 3/5LC0 were selected for pathological section and liver area measurement to verify the hepatotoxicity of PPVI and PPⅦ. Etabonomics study was then conducted to further explore the mechanism of hepatotoxicity of PPVI and PPⅦ. Lovastatin was used as an inhibitor, and PCR was used to verify the results. Result The result showed that under the condition of sub-lethal concentration exposure, hepatotoxicity-included changes in liver phenotype (liver area), hepatocyte swelling and degeneration, liver cell apoptosis and disturbed biochemical index were observed in zebrafish treated with PPVI and PPVII. Furthermore, the transcriptome was conducted to confirm the toxicity mechanism shared with PPVI and PPVII, and we found that steroid biosynthesis process and the related target genes were mainly affected. While, lovastatin treatment effectively ameliorated PPVII-induced zebrafish liver injury by improving the liver tissue structure and regulate the expression of associated genes including HMGCRA, SREBP, LSS, CYP2R1, PIK3R3A, GDPD1 and PFKFB-2. Conclusion This study was the first investigation to provide the direct evidence of hepatotoxicity of PP Ⅵ and PP Ⅶ in vivo zebrafish model, which were related to the steroid biosynthesis. furthermore, in lovastatin played an important role in protection against hepatotoxicity induced by PPVI and PPⅦ by regulating the cholesterol metabolism.

BACKGROUND Coronavirus disease 2019 (COVID-19) is a new infectious disease, and acute respiratory syndrome (ARDS) plays an important role in the process of disease aggravation. The detailed clinical course and risk factors of ARDS have not been well described. MATERIAL AND METHODS We retrospectively investigated the demographic, clinical, and laboratory data of adult confirmed cases of COVID-19 in Beijing Ditan Hospital from Jan 20 to Feb 29, 2020 and compared the differences between ARDS cases and non-ARDS cases. Univariate and multivariate logistic regression methods were employed to explore the risk factors associated with ARDS. RESULTS Of the 130 adult patients enrolled in this study, the median age was 46.5 (34-62) years and 76 (58.5%) were male. ARDS developed in 26 (20.0%) and 1 (0.8%) death occurred. Fever occurred in 114 patients, with a median highest temperature of 38.5 (38-39)°C and median fever duration of 8 (3-11) days. The median time from illness onset to ARDS was 10 (6-13) days, the median time to chest CT improvement was 17 (14-21) days, and median time to negative nucleic acid test result was 27 (17-33) days. Multivariate regression analysis showed increasing odds of ARDS associated with age older than 65 years (OR=4.75, 95% CL1.26-17.89, P=0.021), lymphocyte counts [0.5-1×10⁹/L (OR=8.80, 95% CL 2.22-34.99, P=0.002);0.5×10⁹/L(OR=36.23, 95% CL 4.63-2083.48, P=0.001)], and temperature peak ≥39.1°C (OR=5.35, 95% CL 1.38-20.76, P=0.015). CONCLUSIONS ARDS tended to occur in the second week of the disease course. Potential risk factors for ARDS were older age (65 years), lymphopenia (≤1.0×10⁹/L), and temperature peak (≥39.1°C). These findings could help clinicians to predict which patients will have a poor prognosis at an early stage.

Background Few studies have compared the yield of reverse transcription polymerase chain reaction (RT-PCR) assays in nasopharyngeal swabs, oropharyngeal swabs, and sputum for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection. Methods We conducted an observational study in Beijing Ditan Hospital, China. Specimens including nasopharyngeal swabs, oropharyngeal swabs, and sputum from confirmed coronavirus 2019 patients were collected for RT-PCR testing. Disease duration was calculated from the date of symptom onset to the date of specimen collection and divided into 3 groups: ≤14 days, 14–21 days, and >21 days. We compared positive rates across the 3 specimens collected. The kappa coefficient was used to evaluate the consistency of RT-PCR results between different specimens. Results A total of 291 specimens were collected and tested from 43 confirmed patients. Among specimens collected with a disease duration of ≤14 days, the positive rate was highest in sputum (79.2%); this rate was significantly higher than that in nasopharyngeal swabs (37.5%; P = .003) and oropharyngeal swabs (20.8%; P < .001). Similar findings were observed with the disease durations of 14–21 days and >21 days. The consistency of testing results between nasopharyngeal swabs and oropharyngeal swabs was low with the disease durations of ≤14 days and >21 days. The consistency between the sputum and oropharyngeal swabs and between the sputum and nasopharyngeal swabs was very low across all 3 disease durations, with statistical significance. Conclusions Compared with nasopharyngeal swabs and oropharyngeal swabs, sputum had the highest yield of SARS-CoV-2 detection. Nasopharyngeal swabs and oropharyngeal swabs had a similar yield. If sputum is not feasible, a nasopharyngeal swab can be recommended for the detection of SARS-CoV-2, and early testing is needed.

Understanding ecological processes that drive metacommunity dynamics is essential for elucidating the mechanisms of community assembly and for guiding biodiversity conservation. This is especially important in dammed rivers. Here, we examined the taxonomic and functional beta diversity of macroinvertebrates and their underlying drivers in a dammed tropical river and compared the patterns with those in an adjacent undammed river. We found that both taxonomic and functional beta diversities were higher in the dammed river than in the undammed river across wet and dry seasons. The replacement component contributed most to the overall beta diversity for both taxonomic and functional facets, and this component was higher in the dammed river than in the undammed river. In addition, the taxonomic richness difference component was significantly higher in the dammed river in the dry season, but the functional richness difference component showed no difference between the two rivers and between the two seasons. Environmental filtering was the primary driver of total beta diversity and its replacement component, whereas the richness difference component was mainly explained by spatial factors, but these drivers varied in the dammed river in different seasons. Overall, our results indicated that damming induced changes in physiochemical variables (e.g., temperature, conductivity, and nutrients), accompanied by alterations in flow regime and longitudinal connectivity, increased replacement and loss of taxa or traits. These changes have consequently led to alteration of macroinvertebrate taxonomic and functional community dissimilarity and affected the relative effects of environmental and spatial factors on beta diversity and its components. Our study helps understand the ecological processes associated with dam impacts on macroinvertebrate biodiversity and the conservation potential of undammed rivers. In addition, our results showed that taxonomic and functional beta diversities can provide complementary information about dam impacts on riverine biodiversity.

BACKGROUND Most educators affected by the COVID-19 epidemic have had to find the most appropriate teaching approach to deal with this emergency teaching situation, i.e., an approach that can make good use of various teaching resources to achieve high adaptability. According to the characteristics of medical students and the course content of clinical clerkship, we adopted the problem-based learning (PBL) method to redesign the pedagogy of clerkship. At the end of the semester, the feasibility of the PBL teaching model in emergency remote teaching (ERT), which has an impact on students' learning experience and preference, was evaluated. Compared with other countries affected by the COVID-19 epidemic, the outbreak time and recovery time in China are both earlier; thus, the evaluation and feedback of ERT can provide the referential evidence to global educators and institutions. OBJECTIVE The objective of this study was to explore medical students' learning experience in ERT to understand how these positive and negative perceptions influence their learning preferences in different teaching modes and how the PBL model combined digital technology to influence teaching quality. METHODS Among 123 medical students from Jinan University, China, who participated in the questionnaire at the end of the ERT in the clinical clerkship course, 25 volunteered to have a further in-depth interview. We randomly select five veterinary students to participate in the one-on-one in-depth online interview, which was conducted within 30 minutes. After coding of the transcription by the NVivo 12.0 software, the collected qualitative data would undergo a thematic analysis. RESULTS The thematic analysis indicated two main themes. One is that the adoption of PBL is the crucial for overseas medical students to evaluate ERT positively, and is depicted by one sub-theme: positive comment contributions. The other theme is that clinical practice as the core of medical education has a decisive influence on the teaching mode preference of medical students, as depicted by two sub-themes: negative comment contributions; and preference in different teaching methods. CONCLUSIONS Although medical students preferred an offline teaching mode due to practical requirements, they generally gave positive comments on this ERT because of the PBL method pedagogy. This indicated the feasibility of the online PBL teaching method in medical education. Moreover, medical students' preferences in the combination of the online and offline teaching mode revealed a revolutionary new direction of revolution in medical education.

Impacts of atmospheric cold plasma (ACP) on the properties of muscle protein and performance of extracted crude enzyme of hairtail (Trichiurus Lepturus) fish have been evaluated. A decrease in extracted crude enzyme activity with increasing the ACP treatment time has been found, and the highest reduction (p 0.05) value of 0.035 units/mg proteins was obtained after 240 s. A considerable increase in the carbonyl content in the treated sample for about three times higher than the control sample was found, and a decrease of total sulfhydryl content to 0.34 nmol/mg protein. Texture profile analysis, water holding capacity, and the color properties of the muscle protein improved significantly in the samples treated with ACP. SDS-PAGE pattern showed an increase in the band intensity of cross-linked myosin heavy chains and actin proteins. Based on these outcomes, ACP could play a significant role as a promising non-thermal method to prolong the shelf-life of hairtail fish.

We present that activation of CoMoO

On entering sensory ganglia, herpes simplex viruses 1 (HSV-1) establishes a latent infection with the synthesis of a latency associated transcript (LAT) or initiates productive infection with expression of a set of immediate early viral proteins. The precise mechanisms how expression of α genes is suppressed during the latency are unknown. One mechanism that has been proposed is illustrated in the case of ICP0, a key immediate early viral regulatory protein. Specifically, the 2 kb LAT intron is complementary to the 3′ terminal portion of ICP0 mRNA. To test the hypothesis that accumulation of LAT negatively affects the accumulation of ICP0 mRNA, we inserted a DNA fragment encoding two poly(A) sequences into LAT to early terminate LAT transcript without interrupting the complementary sequence of ICP0 transcript (named as SR1603). Comparisons of the parent (SR1601) and mutant (SR1603) HSV-1 viruses showed the following: Neurons harboring latent SR1603 virus accumulated equivalent amounts of viral DNA but higher amounts of ICP0 mRNA and lower amounts of LAT, when compared to neurons harboring the SR1601 virus. One notable difference between the two viruses is that viral RNA accumulation in explanted ganglia harboring SR1603 virus initiated significantly sooner than that in neurons harboring SR1601 virus, suggesting that ICP0 may act as an activator of viral gene expression in permissive cells. Collectively, these data suggest that increased ICP0 mRNA by suppressed LAT did not affect the establishment of latency in latently infected murine ganglia. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12250-020-00287-2) contains supplementary material, which is available to authorized users.

This paper explores the methods and applications of intuitive visualization and interactive analysis of medical domain knowledge to help medical experts editing it autonomously. SissiExpression system is developed using C# and WPF technology, in which, medical knowledge is modeled as expression. The application of knowledge and execution process is clear and visible, the work of debugging and maintenance is convenient, so the result can be understood and gain recognition by experts. Expressions and knowledge are saved in XML file format, decoupled from program framework, subsequent maintenance, adding new knowledge and functions, can be achieved agilely, conveniently, with better cost control. Appropriate knowledge edition can be chosen flexibly according to demand, medical experts can possess their personal executable knowledge base. This program can help medical experts to mitigate human-computer interaction obstacles to some extent, both medical and information experts can focus on their own profession and tasks.

Additional file 1 : Supplementary Table 1. Dynamic variations in cell counts of total WBCs, total lymphocytes, and lymphocyte subsets in patients with non-severe COVID-19, severe COVID-19, and severe influenza A at weeks 1, 2, 3, and 4. Values represent P values.

In this work, acrylonitrile copolymers were prepared via precipitation polymerization. The copolymer solutions prepared at various ratio of dimethyl sulfoxide and dimethylacetamide were tested to prepare the nascent fibers by one-step wet-spun method. The effect of temperature, solvent ratio, molecular weight and the solid content on the rheological properties of polyacrylonitrile gel solution in different mixed solvent were studied. It was shown that the viscosity decreased with the increase of the temperature and fluctuated with the different solvent ratio reaching the minimal value at the ratio of dimethyl sulfoxide to dimethylacetamide equal to 1.25. The crystallinity of copolymers and the structure of the nascent fiber surface also depended from the solvent ratio in polymerization. The optimum conditions for spinnability of copolymers were determined. The high-quality polyacrylonitrile precursor was achieved with the controllable range of 0.5–0.8 dtex and the toughness of polyacrylonitrile precursor was greater than 6.0 cN/dtex after the wet spinning process, while the tensile strength of carbon fiber is up to 6.25 GPa after their pre-oxidation and carbonization process.

The interior microstructures of polyacrylonitrile nascent fibers is studied by the scanning electronic microscopy and the high-resolution transmission electron microscopy through ultrasonic etching and ultrathin sectioning. Due to the orientation and fold of molecular chains, the lamellae of 50–80 nm in thickness are formed. A high number of pores, ranging from dozens to two hundred nanometers in diameters exist between the lamellae, which result from residual solvent. The fibril structure is formed in the nascent fiber during the coagulation process, which are oriented along the fiber axis. An uneven tensile stress distribution leads to the formation of skin-core structures in the nascent fiber during the dry-jet wet spinning process.

Bamboo, with its fast growth rate and outstanding mechanical properties, has received increasing attention as a green material for engineering applications. Compared to other mechanical properties, little is known about fracture toughness, especially the toughening mechanism of bamboo. In this study, the Mode I interlaminar fracture toughness of bamboo with different proportions of fiber cells (FCs) and parenchyma cells (PCs) was tested, using in situ SEM to investigate the intrinsic mechanisms and extrinsic mechanisms at the cellular level. The results showed that both initiation and crack growth energies of high fiber density region were the lowest, and the crack growth energy of middle fiber density region was the highest. The intrinsic toughening in bamboo is associated with plastic zone size and crack kinking which are governed by PCs. The extrinsic toughening is related to fiber bridging which is governed by FCs. Having the highest fracture toughness, the middle region of bamboo may be the best choice of natural fiber for manufacturing high performance green composite materials. This work fills the gaps in the knowledge of fracture toughness and mechanisms of bamboo, which is vital to the utilization of bamboo in the structural applications. Keywords: Bamboo, Fracture toughness, Intrinsic mechanisms, Extrinsic mechanisms, Fiber bridging

Elevated nitrogen (N) deposition can alter the composition and availability of soil phosphorus (P) and thus affect long-term plant growth. However, it remains elusive whether this effect differs between legume and non-legume forest ecosystems, which have distinctly different abilities to use N and P. In this study, soil P fractions were measured in a legume (Acacia auriculiformis) and a non-legume (Eucalyptus urophylla) plantation in subtropical China, after four-years of N addition. Results showed that the concentrations of soil total P, total Po, and NaOH-Pi (Po and Pi are organic and inorganic P, respectively) were significantly higher, but soil NaHCO3-Po was significantly lower, in the legume plantation compared to the non-legume plantation. Nitrogen addition significantly decreased soil labile P fractions (i.e. NaHCO3-Pi and NaHCO3-Po) in the legume plantation, but they did not change in the non-legume plantation. In contrast, intermediate P fractions (i.e. NaOH-Pi and NaOH-Po) significantly increased with N addition in the legume plantation, but only NaOH-Po experienced a small increase in the non-legume plantation. The recalcitrant P fractions were not significantly influenced by N addition in either plantation. Due to the greater decrease in labile P in the legume plantation, our results suggest that N deposition may lead to greater P limitation in legume plantations compared to non-legume plantations.

Vibrio parahaemolyticus is an important cause of foodborne gastroenteritis globally. Thermostable direct haemolysin (TDH) and the TDH-related haemolysin are the two key virulence factors in V. parahaemolyticus. Vibrio pathogenicity islands harbour the genes encoding these two haemolysins. The serotyping of V. parahaemolyticus is based on the combination of O and K antigens. Frequent recombination has been observed in V. parahaemolyticus , including in the genomic regions encoding the O and K antigens. V. parahaemolyticus serotype O4:K12 has caused gastroenteritis outbreaks in the USA and Spain. Recently, outbreaks caused by this serotype of V. parahaemolyticus have been reported in China. However, the relationships among this serotype of V. parahaemolyticus strains isolated in different regions have not been addressed. Here, we investigated the genome variation of the V. parahaemolyticus serotype O4:K12 using the whole-genome sequences of 29 isolates. We determined five distinct lineages in this strain collection. We observed frequent recombination among different lineages. In contrast, little recombination was observed within each individual lineage. We showed that the lineage of this serotype of V. parahaemolyticus isolated in America was different from those isolated in Asia and identified genes that exclusively existed in the strains isolated in America. Pan-genome analysis showed that strain-specific and cluster-specific genes were mostly located in the genomic islands. Pan-genome analysis also showed that the vast majority of the accessory genes in the O4:K12 serotype of V. parahaemolyticus were acquired from within the genus Vibrio . Hence, we have shown that multiple distinct lineages exist in V. parahaemolyticus serotype O4:K12 and have provided more evidence about the gene segregation found in V. parahaemolyticus isolated in different continents.